CellCom/Freespeak Terminology 

DECT

DECT (Digital Enhanced Cordless Telecommunications) is a digital wireless telephone technology that is expected to make cordless phones much more common in both businesses and homes in the future. Formerly called the Digital European Cordless Telecommunications standard because it was developed by European companies, DECT's present name reflects its global acceptance. Like another important wireless standard, Global System for Mobile communication (GSM), DECT uses time division multiple access (TDMA) to transmit radio signals to phones. Whereas GSM is optimized for mobile travel over large areas, DECT is designed especially for a smaller area with a large number of users, such as in cities and corporate complexes. A user can have a telephone equipped for both GSM and DECT (this is known as a dual-mode phone) and they can operate seamlessly.

 

G.722

G.722 is a ITU-T standard wideband speech codec operating at 32-64 kbit/s. Technology of the codec is based on split band ADPCM.G.722.1: offers lower bit-rate compressions. A more recent variant, G.722.2, also known as "Adaptive Multirate Wideband" (AMR-WB) offers even lower bit-rate compressions, as well as the ability to quickly adapt to varying compressions as the network topography mutates. In the latter case, bandwidth is automatically conserved when network congestion is high. When congestion returns to a normal level, a lower-compression, higher-quality bit rate is restored.G.722 and its variants sample audio data at a rate of 16kHz, double that of traditional telephony interfaces, which results in superior audio quality and clarity.
TDMATDMA (time division multiple access) is a technology used in digital cellular telephone communication that divides each cellular channel into three time slots in order to increase the amount of data that can be carried. TDMA is used by Global System for Mobile communications (GSM), and Personal Digital Cellular (PDC).  An alternative multiplexing scheme to FDMA with TDMA is CDMA (code division multiple access), which takes the entire allocated frequency range for a given service and multiplexes information for all users across the spectrum range at the same time. TDMA is also used for Digital Enhanced Cordless Telecommunications (DECT).   QPSKQPSK (Quadrature Phase-Shift Keying) is a method of digital communication in which the phase of a transmitted signal is varied to convey information. There are several methods that can be used to accomplish PSK. The simplest PSK technique is called binary phase-shift keying (BPSK). It uses two opposite signal phases (0 and 180 degrees). The digital signal is broken up timewise into individual bits (binary digits). The state of each bit is determined according to the state of the preceding bit. If the phase of the wave does not change, then the signal state stays the same (0 or 1). If the phase of the wave changes by 180 degrees -- that is, if the phase reverses -- then the signal state changes (from 0 to 1, or from 1 to 0). Because there are two possible wave phases, BPSK is sometimes called bi-phase modulation. More sophisticated forms of PSK exist. In m-ary or multiple phase-shift keying (MPSK), there are more than two phases, usually four (0, +90, -90, and 180 degrees). If there are four phases (m = 4), the MPSK mode is called quadrature phase-shift keying or quaternary phase-shift keying (QPSK), and each phase shift represents two signal elements. In MPSK, data can be transmitted at a faster rate, relative to the number of phase changes per unit time, than is the case in BPSK.
E1 ProtocolE1 (or E-1) is a European digital transmission format devised by the ITU-TS and given the name by the Conference of European Postal and Telecommunication Administration (CEPT). It's the equivalent of the North American T-carrier system format. The E1 signal format carries data at a rate of 2.048 Mbits per second and can carry 32 channels of 64 Kbps* each. E1 carries at a somewhat higher data rate than T-1 (which carries 1.544 million bits per second) because, unlike T-1, it does not do bit-robbing and all eight bits per channel are used to code the signal.